Support getting distinct level attacks from LearnableAttacks.

Signed-off-by: Deukhoofd <Deukhoofd@gmail.com>

src/Library/CreatureData/LearnableAttacks.cpp

@@ -10,5 +10,5 @@ void LearnableAttacks::AddLevelAttack(uint8_t level, const AttackData* attack) {
         levelData = {attack};
         _learnedByLevel.Insert(level, levelData);
     }
-    _distinctAttacks.insert(attack);
+    _distinctLevelAttacks.insert(attack);
 }